Process of and apparatus for making gas



(Ho Model.) A 2 Sheets-Sheet 1.

L. STEVENS. PROCESS OF AND APPARATUS FOR. MAKING GAS. N0. 570,-516f Patented Nov. 3, 1896.

2 Sheets-Sheet 2.

(No Model;)

L STEVENS PROCESS or AND APPARATUS FOR MAKING (ms.

' No. 570,516. Patented'Nov. 3-, 1896.

UNITED STATES PATENT OFFICE.

LEVI STEVENS, OF TRENTON, NEW JERSEY.

PROCESS OF AND APPARATUS FOR MAKING GAS.

SPECIFICATION forming part of Letters Patent No. 570,516, dated November 3, 1896.. Application filed December 13, 1895. Serial No. 572,023. (No model.)

To all whom, it may concern:

Be it known that I, LEVI STEVENS, a citizen of the United States, residing at Trenton, in the county of Mercer and State of New Jersey, have invented certain new and useful Improvements in Processes of and Apparatus for Making Gas, of which the following is a specification, reference being had therein to the accompanying drawings.

My invention relates to an improved process of and apparatus for making carbureted water-gas from bituminous coal, lignite coke, or hard coal.

The object of the process and of the con struction and adaptation of the various parts in such combination is that the different products of soft coal or equivalent material are utilized and a close compact body of coke is maintained in the generating-zone of the generator.

The novel features constituting my invention will be described hereinafter, and particularly pointed out in the claims.

Figure 1 is a vertical section through the generator, combustion, carbureting, and vaporizing chambers, retort, superheater, super- .heating-chamber, steam-boiler, and oil-tank,

with all the various connections and passages. Fig. 2 is a section through the generator on line C C. Fig. 3 is a section between the retort and superheating-chamber, showing gas ports or passages connecting retort and superheating-chambers. Fig. 4 shows the perforated distributing-coil that delivers the oil upon the hot surfaces forming the vaporizing-chamber. Figs. 5 and 5 are horizontal and sectional plans of steam-superheater, showing its mechanical construction and arrangement.

I have shown the apparatus in Fig. 1 mainly in central vertical section, which illustrates the relative position and construction of the various parts.

Thegenerator G and the superheater, with their immediate accessories, as I have shown them in the drawings, are inolosed in brickwork of suitable heat-resisting quality. The

4 generator, which is in the form of two truncated cones set base to base, is made tapering, the horizontal line a Ct being of the greatest diameter. The important relations of these tapering parts to the greatest diameter are as hereinafter more fully explained, although these properties may be varied somewhat without departing from the spirit of my in vention. This generator is surmounted by a magazine m, joined to the top of the generator and having mechanical feeding devices adapted to maintain suitable pressure upon the coal or other fuel and properly feed it to the generator as the coke is consumed in the working-zone. The ,magazine is shaped and arranged to supply the coal directly to the center of the generator-chambe1a The blast from the chamber below the grate g generates the heat which passes up through the mass of coal.

Around the magazine m are passages j, lead ing from the generator to a horizontal annular chamber about the magazine, which chamber extends as an outlet-passage and forms a combustion,carbureted,and vaporizing chamber L L. Over this chamber is a large opening through the top arch, through which any deposit of carbon may be removed. An annular perforated pipe V is located immediately over this opening, and it is surrounded by a cover, to which is suspended a block of refractory material which hangs in the opening, but is of less diameter, so as to leave an annular passage about it. The block protects the ironwork from excessive heat, and also acts as aweight to hold the cover,which thus can act as a safety-valve in case of explosion in any part of the apparatus. The carbureting-vapor passes to the carburetingchamber through the annular passage about the block, as above described.

Seen on the right of Fig. 1 is the retort U, inclosed in the same brickwork and to be filled with coke, fire-brick, or refractory ma terial loosely placed to permit the passage of gas downward. In the bottom of the retort are ports 71, Fig. 3, leading to an annular chamber 0, which is surrounded by a steamsuperheaterwith zigzag passages throughout, as shown in Figs. 5 and 5. From the passages in this annular chamber 0 a passage P leads to a boiler B, entering at the bottom, and from the bottom is an unobstructed passage upward through the tubes and through pipe S to the hydraulic main.

An. air pipe I-I, provided with a valve, (closed when the steam is on,) leads from a suitable blower to the space under the grate of the generator. Another passage P leads from the steam-superheater to the chamber under the grate. A pipe F, provided with a valve, leads from the carbureting-chamber to the air-pipe II.

From the boiler a valved pipe q leads to the zigzag passages of the superheater. Pipe 1 is in connection with the perforated annular pipe above the carbureting-chamber, leading from a coil 4, inclosed over a passage 3, opening from the retort, and this coil is supplied by a pipe 25 from a tank T, into the bot tom of which it is extended from the top. The tank is closed and is supplied through pipe 4" from a suitable pump. The pipe t is connected by another valved pipe a, extending to the steam-pipe q for purging the coil and its connections. The carburetant passes in the pipe 25 to the coil r and from the coil 7* to the perforated annular pipe, by means of which it is sprayed, and then passes to the chamber L.

In the carburetirig-chamber is a door g. In the passage leading to the chimney E is a valve E.

The feeding apparatus may be of any convenient form. I have shown a rotary shaft carrying a screw Z.

The problem of utilizing the fixed carbon of bituminous coal in making water-gas and the volatile hydrocarbons for gas illuminating or heating by a single process has been a difficult one. To make water-gas by passing steam through a body of incandescent carbon requires the carbon to be close and compact or a large percentage of the steam will pass through without being disassociated. The effect of coking coal under conditions where a portion of its bitumen has not been expelled and the coke is not kept in motion is'to crack and form fissures through the entire mass. Then the air-blast is applied, the air follows these fissures, enlarging them. \Vhen the steam is applied, it follows where there is the least resistance through these channels formed in coking and by the airblast, and a large percentage passes through as steam and is carbureted with the gas. The heat in the retort not being sufficient to convert its oxygen into an oxid with the carbon of the oil, both are deposited in the condenser as a waste product, having taxed the heat and energy of the steam-boiler, retort, and gas-generators without results, except a waste of material.

\Vith the arrangement of apparatus and process herein described the coal is automatically supplied to the magazine and from the magazine to the generator as the coal or coke is consumed by the process therein. The coal as it descends is gradually raised in temperature and the heat from the products of combustion, in blowing up a heat, and the hot gases in making water-gas, heat and coke the coal between the generating-zone and the outlet gas-ports' The fresh coal from the magazine assumes the form of an inverted cone, from which the volatile bituminous portions are expelled and forced through the surrounding mass of hot coke, where the heavy bitumen is deposited and the more volatile portions pass on as gas to carburet the water-gas or be consumed for heating the carbureting-chamber, retort, superheater, and steam-boiler.

The form and proportions of the generator, magazine, and mechanical feeding device are essential features in carrying out my process most satifactorily. WVhile the form and proportions can be varied, I have found the most satisfactory results in a generator where the lower section from the grate-bars to a line a a is one-half the greatest diameter of the genorator which is at the line a a. The upper section from the line a a to b b at the top is the diameter of the generator at a a. The magazine may be any height preserving its conical proportions that allows the coal to pass down unobstructed. A generator constructed on these lines and proportions witha feeding device that can be regulated to supply ooal to the magazine, as it is consumed in the generator, will always maintain a close compact body of coke, through which it is impossible to get steam that has been previously heated to a temperature of from 800 to 1,000 Fahrenheit without its being disassociated.

In starting this apparatus a fire is built on the grate-bars. Valve E is opened to give draft. The lower section of the generator is filled with coal and allowed to burn until the coal is coked and thoroughly incandescent, when the upper section is filled with coal to the bottom of the magazine and allowed to coke and burn until the apparatus has become heated in all its parts. The Valve in air-pipe F should be opened and the gases ignited in the combustion-chamber, which can be done by opening a door g, when coal should be supplied, if necessary, to the generator and the apparatus allowed to run on draft until there are fifteen pounds of steam on the boiler. Then the magazine should be filled with coal and the engine and blower put into operation. The air-blast will raise the temperature in the generator and steam in the boiler, when the air-blast and valve E are closed. Steam is turned onto the superheater by opening valve I. In passing through the zigzag passage of the superheater its temperature will be raised to 800 Fahrenheit. At this temperature the oxygen of the steam will be given up to the carbon as CO, liberatin g the hydrogen,which, passing up through the coke and coal in the upper section, will take on the volatile parts remaining and pass out through ports jj to annular chambers around the magazine to the outlet-passage K K to the carbureting-chambers L L, where it meets oil-vapor from the vaporizing-chamber. From the carbureting-chamber the gas passes to the retort U, (which is filled with coke, fire-brick, or any refractory material,) to ports n 91., through ports at n to annular chambers 0 0, through passages P P to boiler, through the boiler-tube to outlet-passages S S, to the hydraulic main.

The steam-superheater is an important fac tor. I have found this most difficult to make. It must resist the action of oxygen at a temperature of l,600 Fahrenheit in order to deliver steam to the generator at from 800 to 1,000 Fahrenheit.

The construction of the superheater is shown in Figs. 5 and 5. This superheater is annular in form and is composed of sections which are the segments of the ring form and which, when put together, assumes the annular form shown in Fig. 5. Each section S has a vertical passage 25, communicating with a horizontal passage u, on top, opening in one direction and a like passage at the bottom opening in the other direction, so that when the parts are together they form a zigzag passage. In the bottom passage is a chamber '0 to receive the sand and scale from the casting, so as not to obstruct the passage. Two castings form a divisional wall entirely across, as shown at o, and the inlet and exit passages are on each side, as shown in Fig. 5

The location of the superheater in a chamber below the retort protects it against the possibility of its being destroyed on the outside by free oxygen. Being protected against the action of oxygen 'on its inner surface and being located in a chamber where no free oxygen can reach it when at a high temperature, it is nearly indestructible.

WVith this construction of a generator and superheater and the combination of carbureting-chamber, retort, boiler, and oil supply 2. In a gas-producing apparatus, a generator, combined with a central magazine having passages between said magazine and the walls of the generator with a mechanical feeding device, constructed to feed the coal under pressure to the magazine and generator, substantially as described.

3. In a gas-producing apparatus, the combination of a generator, and retort, with a connecting-passage between them, forming a combustion, carbureting and vaporizing chamber, said passage having an outlet at the top, a coil for the oil supply, a loose cover for said carbureting-chamber and coil, and a weighted block of refractory material suspended from the cover which makes a relief or safety valve in case of an explosion, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

LEVI STEVENS. \Vitnesses:

HENRY E. COOPER, F. L. MIDDLETON. 

